Electrical switch



Jime 24, 1924. ,A 1,498,817

` J. H. SMITH v ELECTRICAL SWITCH Filed May 2O, 1922 Patented june 24, 1924.

UNITED .STATES JOHN HENDERSON SMITH, OF CHARLOTTESVILLE, VIRGINI.

ELECTRICAL SWITCH.

Application led May 2o, 1922. serial No. 562,408.

To all whom t may concer/11:

Be it known that I, JOHN HENDERSON SMITH, a citizen of the United States, residing at Charlottesville, in the county of Albemarle and State of Virginia, have invented certain new and useful Improvements in Electrical Switches, of which the following is a specification.

This invention relates to electrical switches, and more particularly to rotary switches.

In the present construction of rotary switches, there is provided a bushing adapted to receive a rotating member. The rotating member is held in place by a spring and is held sufficiently tight to prevent accidental movement but is free to move when pressure is applied thereto. The rotating member or stem is provided with a washer arranged adjacent the top of the bushing, and adapted to be held in contact with the face of the bushing by the tension of the spring to retain the member in proper position.

I have found that euch construction is disadvantageous, in that the washer loosens from the stem and permits the rotating member to move from one position to another.

In the present invention, I provide a washer or collar formed integral with the stem. The lower end of the stem is reduced, forming a shoulder and the reduced portion is threaded for the reception of a nut. By providing` a shoulder to limit the inward movement of the nut, the tension of the spring may be pre-arranged and the provision of an integral collar engaging the face of the bushing maintains the proper tension on the rotating member at all times.

In the accompanying drawings, I have shown one embodiment of the invention. In this showing:

Figure l is a front elevation of portion of a panel board showing the invention applied,

Figure 2 is a vertical sectional view on line 2 2 of Figure l, and,

Figure 3 is a perspective view of the rotating member detached.

Referring to the drawings, the reference numeral 1 designates a panel board of the usual construction, having a plurality of spaced concentric contact members arranged thereon. The panel board is provided with an opening adapted to receive a bushing 3.

at 11, forming a shoulder 12. A coil spring f 13 is arranged around the rotating member, one end of the coil spring engaging the lower face of the bushing and the other end engaging a nut 14 arranged on the threaded portion 11 of the stem. The tension of the spring draws the rotating member inwardly into the bushing. A nut lock 15 may be arranged on the end of the reduced portion to retain the nut 14 in position.

The. rotating stem is provided with an integrai collar or washer 16 which is adapted to engage the collar e of the bushing and thus ret-ain the switch in a set position. Beyond the collar, the stem is threaded,l as at 17, and is adapted to receive a handle or knob 18, of insulating material. This lrnob is provided with a central opening having a metallic ferrule 19 arranged therein, and the ferrule is provided with threads adapted to engage the threads which engage the stem.

The operation of the device will be apparent from the foregoing description. The collars e and 1G are held in frictional engagement by the spring, preventing accidental movement of the switch from a selected contact 2. The friction, however, may be overcome by pressure, and the switch may be moved to another contact by turning the knob 18. By providing a collar formed integral with the stem 9, the possibility of the collar or washer becoming loose and thus permitting the stem to rotate freely is overcome. The length of the stem between the collar and the shoulder is predetermined to place a definite desired pressure on the stem when the spring 13 is placed in position and the nut 14 tightened. By providing a shoulder, the inward movement of the nut 14 is limited and the tension of the spring 13 predetermined.

It is to be understood that the form of my invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape7 size, and arrangement of parts may be resorted to Without departing from the spirit of the invention or the scope of the subjoined claim.

Having thus described my invention, I claim:

In a rotating switch, a bushing adapted to be arranged in a suitable support, said bushing being provided with a central openn ing and having a collar formed on its outer end, a vrotating element arranged in said opening and projecting beyond the ends of the-bushing, the outer end of said element being provided with an integral enlarge- 15k ment adapted to contact with the collar of Vof said spring engaging the inner end of the bushing, and a nut arranged on the reduced portion of the rotating element adapted to form a stop for said spring In testimony whereof, afx my signa- `ture in presence of two Witnesses.

'JOHN HENDERSON SMITH;Y

Witnesses:

GEO. E. PRICE, 

